Save $119.00 on our Cairns Family Great Barrier Reef Tour Deal. 2nd Child Travels Free. Great Barrier Reef tours depart Cairns daily to the new outer Great Barrier Reef pontoon that has the Spaghetti Slide that everyone is talking about. This reef trip offers a few extras other reef trips do not. A huge range of free activities from Glass bottom boat tours to Semi-submersible submarine tours and if you are a non-swimmer or have young children or elderly friends then this is the perfect Cairns Great Barrier Reef tour. You can even do scenic helicopter flying tours from this pontoon or you can fly from Cairns and return to Cairns by boat.